//
//  ViewController.m
//  CoreData
//
//  Created by dllo on 15/11/20.
//  Copyright (c) 2015年 dllo. All rights reserved.
//

#import "ViewController.h"
#import "CoreDataManager.h"
#import "Student.h"

@interface ViewController ()

- (IBAction)add:(id)sender;

@property(nonatomic, strong) CoreDataManager *manager;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    self.manager = [CoreDataManager defaults];
    
    NSLog(@"url = %@", [self.manager applicationDocumentsDirectory]);
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

// coreData添加方法
- (IBAction)add:(id)sender {
    
    // 创建 实体描述类
    // 参数1: 描述的实体
    // 参数2: 数据管理器
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Student" inManagedObjectContext:self.manager.managedObjectContext];
    
    // 创建实体
    // 参数1: 实体描述
    // 参数2: 数据管理器
    Student *stu = [[Student alloc] initWithEntity:entity insertIntoManagedObjectContext:self.manager.managedObjectContext];
    
    stu.name = @"成精";
    stu.age = @1000;
    stu.sex = @"?";
    stu.number = @213;
    stu.hobby = @"吹牛13";
    
    [self.manager saveContext];
}

// 查找
- (IBAction)select:(id)sender {
    
    // 获取查询数据的请求, 相当于数据库的查询语句
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
    
    // 添加约束 谓词
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"name", @"%@"], @"成精"];
    
    request.predicate = predicate;
    
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error;
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    
    NSLog(@"%ld", array.count);
    
}

// 修改
- (IBAction)change:(id)sender {
    
    // 查找
    // ************************************************
    // 获取查询数据的请求, 相当于数据库的查询语句
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
    
    // 添加约束 谓词
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"name", @"%@"], @"成精"];
    
    request.predicate = predicate;
    
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error;
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    // ************************************************
    
    Student *stu = [array lastObject];
    stu.sex = @"好像大概应该差不多可能约么也许是女的吧";
    
    [self.manager saveContext];
    
}

// 删除
- (IBAction)delete:(id)sender {
    
//    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
//    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"sex", @"%@"], @"?"];
//    request.predicate = predicate;
//    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"sex" ascending:YES];
//    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
//    NSError *error;
//    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    
    
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Student" inManagedObjectContext:self.manager.managedObjectContext];
    [fetchRequest setEntity:entity];
    // Specify criteria for filtering which objects to fetch
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"sex", @"%@"], @"?"];
    [fetchRequest setPredicate:predicate];
    // Specify how the fetched objects should be sorted
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"sex"
                                                                   ascending:YES];
    [fetchRequest setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error = nil;
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:fetchRequest error:&error];
    
    for (Student *stu in array) {
        [self.manager.managedObjectContext deleteObject:stu];
    }
    
    [self.manager saveContext];
}

@end
